Timing and drive means for stitching apparatus



March 16, 1965 P. J. HE

Filed July 17, 1963 RBST TIMING AND DRIVE MEANS FOR STITCHING APPARATUS '7 Sheets-Sheet 1 March 16, 1965 P. J. HERBST 3,173,592

TIMING AND DRIVE MEANS FOR STITCHING APPARATUS Filed July 17, 1965 7 Sheets-Sheet 2 March 16, 1965 P. J. HERBST TIMING AND DRIVE MEANS FOR STITCHING APPARATUS '7 Sheets-Sheet 3 Filed July 17, 1963 March 16, 1965 P. J. HERBST 3,173,592

TIMING AND DRIVE MEANS FOR sTITcHING APPARATUS Filed July 1'7, 1965 '7 Sheets-Sheet 4 March 16, 1965 P. J. HERBST 3,173,592

TIMING AND DRIVE MEANS FOR STITCHING APPARATUS Filed July 17, 1965 '7 Sheets-Sheet 5 March 16, 1965 P. J. HERBST 3,173,592

TIMING AND DRIVE MEANS FOR STITCHING APPARATUS Filed July 17, 1963 7 Sheets-Sheet 6 P. J. HERBST 3,173,592

TIMING AND DRIVE MEANS FOR STITCHING APPARATUS March 16, 1965 'I Sheets-Sheet 7 Filed July 17, 1963 HTF United States Patent O 3,173,592 TIMING AND DRIVE MEANS FOR STITCHING APPARATUS Philip J. Herbst, Mount Wolf, Pa., assigner to St. Regis Paper Company, New York, NY., a corporation of New York Filed July 17, 1963, Ser. No. 295,663 3 Claims. (Cl. 227-7) This invention relates to timing and drive means for stitching apparatus. The invention is more particularly adapted, among other possible uses, for driving and controlling the timing of thefoperations of stitching apparatus of types adapted, for example, to apply a succession of Wire staples for stapling together the overlapping edges of corrugated paperboard carton blanks as customarily stitched by such staples to form one of the vertical corner joints of such containers.

The operation, controlling and timing of such apparatus involves means for starting the operation at the proper moment when the intended joint areas of a collapsed carton, for example, are brought into position to receive the staples.l Pull rolls should be provided for quickly bringing the carton blank with the joint to such position, whereupon the carton should be further advanced for a predetermined short distance to bring the desired area for the first staple to the location where a stitcher head drives the staples into place while the carton is momentarily stationary. Then the carton must be quickly advanced for a predetermined distance, representing the spacing to the next staple and then abruptly stopped again and similary started and stopped for the succeeding staples until a predetermined number have been applied to complete the desired carton joint.

The dimensions of different cartons, for course, may be such as to require different numbers of staples to complete the joint and the carton specifications may require that the spacing of the staples be different for different types of cartons. Iny other cases it may be desired to operate the apparatus continually for extended intervals for stapling together long strips.

Heretofore such stitching machines, as now widely used for forming the joints in corrugated paperboard cartons, have necessarily had quite elaborate and complicated mechanical control mechanisms for driving the apparatus and properly timing its operations and doing so while being so constructed as to permit of the necessary adjustments for different spacings of the staples and for applying different numbers thereof.

The present invention makes possible equipment for generally similar purposes, but which is largely so controlled electrically as to involve a very substantially similar number of parts, economical to construct and assemble and so arranged that the necessary altered adjustments may be quickly and accurately made, and the equipment operated at a low expense for maintenance.

The invention makes possible, in addition to the irnproved timing and driving facilities, a highly accurately controlled arrangement for feeding the carton blanks past the stitcher-head.

The features of the present invention are also Well adapted to be manufactured and furnished as an assembly or kit which may be used to replace the mechanical timing and drive facilities or existing stitcher machines.

Various further and more specific objects, features and advantages of the invention will appear from the description given below, taken in connection with the accompanying drawings, illustrating by way of example a preferred form of the invention.

In the drawings:

FIG. 1 is an elevational view showing in general out- ICE line a known form of stitcher machine but with certain of the parts replaced by the features involving the present invention;

FIG. 2 is a top view of the machine of FIG. 1, certain parts being broken away;

FIG. 3 is an elevational view, partly in section, and showing the principal elements and their relationship in that part of the machine which drives and controls the timing thereof;

FIG. 4 is a vertical sectional view taken substantially along line 4-4 of FIG. 3;

FIG. 5 is a sectional View showing certain of the operating parts, this view being taken along line 5*-5 of FIG. 3;

FIG. 6 is a broken sectional View taken substantially along line 6--5 of FIG. 5;

FIG. 7 is an enlarged vertical sectional view showing certain of the parts in section as taken substantially along line 7-7 of FIG. l and showing the parts at their location when a collapsed carton is about to be fed into position for stitching;

FIG. 8 is an elevational view, partly in section, showing certain ofthe parts and taken substantially along line 8-8 of FIG. 7;

FIG. 9 is a view simil-ar to FIG. 7, but further illustrating certain of the parts in their positions when the carton blank has been fed in to a point Where it is about to engage and operate certain target means for initiating the stitching operations;

FIG. 10 is a view similar to FIG. 9, but showing the parts at a later moment;

FIG. l1 is a perspective view further illustrating the parts shown in FIGS. 7-10 inclusive;

FIG. l2 is another perspective View, further showing the relation of certain of the parts during stitching' of a carton blank joint;

FIG. 13 is an enlarged sectional View taken substantially along line 13-13 of FIG. 12;

FIG. 14 is an enlarged sectional View taken substantially along line 14-14 of FIG. 12; and

FIG. l5 is a diagram of the electrical control circuits for the apparatus of the invention.

Referring now to the drawings in further detail, the machine, as shown in FIG. 1, is mounted upon a stand having supporting arm portions 21 and 22 extending to either side; also a bracket-shaped arm 23 which extends upwardly from the arm 22 and thence to the left for supporting a stitching head 24, having a portion as at 25 for driving staples to form a carton joint. This stitching head may be of a well known type, embodying per se none of the features of the present invention. It may be driven by a shaft as indicated by dotted lines at 26 in FIGS. l and 3.

A corrugated paperboard carton blank is indicated in various of the figures at 27 as same is being progressed through the machine while overlapping portions thereof are being stapled together to form a corner joint, as best shown at 28 in FIG. 12, and' as stapled together by a plurality of wire staples 29, which have been applied by a known form of staple applicator means, the lower portion of which is indicated at 30`in FIG. l2.

The carton blank is fed beneath the stitcher-head by a plurality of pairs of upper and lower pull rolls 31, 31', and 32, 32 (FIGS. 1 and 12). The upper pull rolls are driven by shafting, as indicated at 33, which preferably contains universal joint means, as at 33 (FIG. l), while the lower pull rolls may be driven by shafting 34 having like universal joint means (see also FIG. 3).

The stitcher-head shaft 26, as well as the pull-roll shafts 33, 34, are driven and controlled by timing equipment (hereinafter described) contained in a cabinet 35 located at the right hand portion of the frame or stand of the machine, as shown in FIG. l, and the interior arrangements of which are best shown in FIG. 3. This operating equipment is driven as by a drive motor 36, mounted upon the top of its cabinet 35. Relays and electrical control elements may be mounted in a cabinet 35 suspended beneath cabinet 35. 4

As shown in FIGS. 3 and 4, the drive motor 36 is arranged topdrive a pulley 37 through a belt 38, the motor being mounted on a suitable vertically adjustable stand, as indicated at 39, to permit the positiony of themotor to be adjusted to adjust the tension in the belt.

Pulley 37 is freely rotatable on stitcher-head shaft 26, and this pulley is also fixed to a sprocket 40 carrying a sprocket chain 41 for driving a sprocket 42, so long as the motor is operated. j

Pulley 37, although Vfreely rotatable on shaft 26, is adapted to be connected thereto by an electromagnetic clutch of a suitable known type, the outlines of which are indicated at 43, and this clutch is accompanied by a suitable known type o f magnetically-operated brake means, the outlines of which are indicated at 44, this brake being so controlled as normally tov hold the stitcher-head drive shaft 26 against rotation, except when the clutch means 43 is connected for driving such shaft through the medium of pulley 37 and the belt-connected` drive motor 36.

' The clutch and brake assemblies herein referred to, may be of well-known types put out by the Warner Electric Brake & Clutch Co., Beloit, Wisconsin.

The upper pull-roll drive shaft 33 is connected to be driven bythe sprocket 42, through a normally engaged electromagnetic clutch means of suitable known type, the outlines of which are indicated at 45. Intermeshing gears 46 and 47 on the pull-roll drive shafts 33 and 34 respectively, normally cause the lower pull-roll shaft to be rotated concurrently with theupper pull-roll shaft. Electromagnetic brake means of a suitable known type, and the outlines of which are indicated at 48, is mounted at the end of shaft 34, this brake being adapted to become engaged, and to resist rotation of this shaft during intervals when the electromagnetic clutch means 45 is disconnected. During these intervals, the pull-roll shafts 33, 34 lare adapted to be step-rotated through angles sufficient to correspond to the spacings of the stitches being applied by the stitcher head. Also during these intervals, the clutch 43 is engaged, and the brake 44 is released, permitting the stitcher-head shaft to be rotated bythe pulley 37. This rotation of shaft 26 through the medium of eccentric and linkage mechanism at 50, 51 and 52, causes pull-roll shafts 33 and 34 to step-rotate during the abovementioned short intervals. This mechanism will now be described in-further detail with reference to FIG. Here it will be noted that the shaft 26 carries an eccentric 53 having an arrn-54 connected to a bell crank 55, which is freely swingable about shaft 33. The lower arm of this bell crank has a link 56 pivotally connected to a block 57, adjustably secured as by screw means 58 within a guideway means 59, which in turn is connected at 60 to a sprag type of clutch of known form, the outlines of which are indicated at 61 in FIG. 3.r By adjusting the screw means 58, the point of pivotal connection lof the block 57 withrespect to link 5S may be adjusted to change the radius of that point with respect to pull-roll shaft 34. Accordingly, when shaft 26 is rotating to actuate the eccentric 53, this will cause, through the linkage here described, the shaft 34 to step-rotate through a predetermined anglejdepending upon the radius at which block 57 is adjusted with' respect to the center of shaft 34, and this adjustment depending upon the desired spacing of the stitches. During the intervals of operation of the eccentric and linkage mechanism 50, 51 and 52, the brake 48 will apply a friction dragging effect to shaft 34, but because of the sprag clutch 61, said mechanism will be able to turn shaft 34, which in turn, through the gears 46, 47, will correspondingly turn the upper pull-roll shaft 33. The latter will be free thus to rotate independently of the main motor drive, because during the time of stitching and step-feed, clutch 45 will be disengaged.

A so-'called cycle-monitor timing device 63 may be mounted withinthe lower right hand corner of cabinet 35. This may be of a readily available, suitable, known type, such, for example, as one .known underrthe tradename of Cyclo-Monitor, put out by Precision Products Controls Inc., of Tulsa, Oklahoma. YSuch devices are adapted to be variously adjusted by presetting, so as to count out a predetermined number of revolutions, which number, inthe present case, depends lupon the number of staples desired to be applied during the operation of the machine for stitching the joint of each carton. Such device may be `adjusted by a thumb-button, as indicated at 64, accompanied by a dial indicating the number of revolutions for which the device is to be preset. (The monitor has an internal adjustment from 0 to 100. The external dial 64 provides for adjustments of 100 revolutions per minute, for example 100, 200, 300 etc.) After preset number of impulses has been counted, the device operates a circuit as hereinafter described for stopping the stapling impulses. This device may be operated (as indicated in FIGS. 3 and 4) by sprocket and chain means 65, 66 and 67, the sprocket 67 being keyed to shaft 26 so that the device will be operative each time that the shaft 26 is rotated for operating the stitching head.

Cycle-monitoring devices of the type above referred to are so constructed that, upon actuation thereof to release the circuits, the device will be in condition immediately to start counting backwards, in effect, an equal predetermined number of actuations of the stitcher-head while the next workpiece is being stapled, and after which the device ywill be ready to repeat its cycle of operations as before. Such devices are adapted to be preset for counting either a small number of impulses, or many hundreds, if desired, in cases where the machine is to be used to 'stitch exceptionally long joints in the workpieces.

As .above stated, the shafting 33, 34 for the pull rolls, embodies universal joints as at 33f, 34. Y These permit themechanism in cabinet 35 to be connected to the pull rolls without undue accuracy of alignment, but more im# portantly, the joints 34 permit the shafting 34 to be adjusted in position somewhat, so kas to adjust the spacing between lthe upper and lower pull rolls, thereby to accommodaite` folding cartons having various different wall thicknesses. To this end, the lower pull-roll shafting 34 may be carried in bearings supported by leverr arms, one of which is best indicated ait 70 in FIG. ll, same being keyed to a shaftl extending in generally parallel relation to shafting 34. Shaft 71 (see FIGS) may be ad` justably turned, thereby variably toI adjust the elevation of the lower pull rolls, by means shown in FIGS. 5 and 6, and comprising a block 72 secured to the shaft and having its ends respectively pivotally connected to rods 73, 74,'.Which extend through'another block 75, secured to `the machine frame. Rods 73 and 74 may have threaded adjustment knobs as at 73', 74', the knob 73 pressingthrough a spring 76, against the block 75. It will be apparent that adjustment of the knob 73 will have the effect of 'turning shaft 71, which in turn rocks levers as at 70 for slightly elevating or lowering the pull-roll shafting 34. j

Reference will now be had .to FIGS.Y12-14 inclusive, illustrating the guiding means for the overlapping joint portions of the canton. Such means may comprise a member 7S' having a recess as at 79 for slidably receiving the underlying edgefportion where the joint `is Ito be formed on the carton. The member 78 may be removably `attached Ito` suitable supporting means as shown at 81 in FIG. 13, and the upper surface 82 of this member slidably supports the overlying joint portion 28 of the carton. The forward end of the member 78, as indicated ait 83, extends inwardly of the path of fthe carton toy support an anvil piece 84 (FIG. 14), so that when the driving means 30 of the stitcher applies a kstaple as at 29,v

its lower points will engage and be turned by the anvil piece 84 into gripping engagement with the overlapping joint portions of the carton. Meanwhile, the opposite wall por-*dons of the canton, as indicated at 8S in FIGS. 14 and l5, will slide along in under the member 83.

Reference will now be had to FIGS. 7-11 inclusive in describing a so-called target member and associated features for controlling the electrical circuits for the operating mechanism. As best shown in FIG. 1l, these parts in general may be mounted upon a rectangular frame structure 86. This structure carries a target plate member 87, extending transversely across the path of the entering carton blanks, and supported on lugs as at 88, which in turn are pivotally mounted on pins as at 89. These pins are surrounded by coil springs 9i), which norm-ally urge the target plate 87 to vertical position, but permit the latter to be swung downwardly when the pull rolls urge a carton blank rmly thereagainst. The target plate 4assembly may be mounted upon a frame 91, which in turn is -slidab-ly mounted in the frame 86. The position of the frame 91 may be adjusted by turning a threaded rod 92. by means of handle 93, this rod having threaded engagement with the frame 91 at a block 94. Frame 91 is normally adjusted so that the target plate 87 will be initially at a position so as to be engaged by the incoming carton blank when the forward edges of the flaps of such blank have moved beyond the stitch applicator` for a predetermined distance. Then, upon the urging of the pull rolls, the forward edges of the canton blank iiaps will act to push the target plate and its frame 91 for a short distance, such as indicated by the arrow 94 in FIG. 10. This will cause a spring 95 on the rC-d 92 to be compressed against the frame S6 by a collar 96, thereby permitting an operating plunger 97 of a microswitch 98 (FIG. 10) to rise, operating this switch, which in turn will start operation of the operating control circuits hereinafter described.

Normally the target plate 87 is held by latch means, which will now be described, to prevent same from pivoting down to allow the carton blank to pass until the moment when the target plate has reached the position shown in FIG. 10. This latch may comprise a square shaft 100 having por-tions rotatably mounted in the frames 86 and 91, and having :a lug 101 appropriately positioned thereon to latch the target plate in vertical position until the shaft 199 is turned and the lug 191 is swung down out of the way. This may be accomplished by means shown in FIGS. 7 and 8, comprising a target latch solenoid 102, connected by linkage generally indicated at 103, having a retaining spring 104, which normally holds the shaft 19t) in a position with the lug 191 `as shown in FIG. 1l, but upon energizing this solenoid, shaft 198 is turned so as to turn the lug 101 down, permitting the target plate 87 to .turn down out of the way of the advancing carton blank at the proper time. After the trailing edge of the carton has passed the region of the target plate, spring 194 will act to turn the latch lug 161 back into normal position as the target plate springs 90 also turn the target plate back to verticatl position.

The control circuits will now be described with reference to FIG. l5. As indicated at the left hand side of this circuit diagram, the circuits may be operated for eX- arnple from a 110 volt, 60 cycle alternating current source, as may also the main drive motor 36, which is in a circuit laccompanied by `a suitable start-button or switch (not shown). As further shown in FIG. l5, the pullroll clutch and brake circuits, as well as the main drive clutch and brake circuits (both of Warner type electric controls), may be operated by direct current supplied through rectiiiers, as at 105, 196 respectively. In this diagram, the magnets of the various relays used are indicated in the conventional way by rectangles accompanied by reference characters, but the contacts which are actuated by each relay magnet are shown at other parts of the diagram yand accompanied by similar reference characters (for example: relay magnet TRS operates contacts TRSa and TRb).

In addition to various relays and relay contacts, and any desirable fuses (not shown) the pull-roll clutch and brake circuit may comprise brake `and clutch operating solenoids, as indicated respectively at 197 and 1&8, with accompanying condensers 109 and 119 and adjustable rheostats as at 111, 112. Similarly the main drive clutch and brake circuits include clutch land brake yoperating solenoids 113, 114 respectively, accompanied by condensers 115 and 116 and rheostats 117 'and 11S.

When the main power supply is initially connected, it will be noted that circuits will be completed such that the main drive brake solenoid 114 is energized, as is also the pull-roll clutch solenoid 108. At this time a hand wheel as at (FIG. 3) on the main drive shaft Z6 shoud be adjusted at an angular position as by a guide pointer with accompanying dial means at 121, such that the stitching means will be in its uppermost position. The main drive motor 36 may then be started as by a startbutton, whereupon by reference to the parts as hereinabove described in connection With FIG. 3, it will be understood that the pull rolls will then be rotated, but the drive shaft 26 for the stitcher head will be held by the brake 44 against rotation.

As a carton blank is fed between the pull rolls, the blank will soon engage the target plate 87, as shown in FIG. 9, and thus the supporting frame for the target plate, by pushing on rod 92, will actuate the microswitch 9S. Now, from the diagram of FIG. 15, it will be noted that this will cause actuation of relay TRS. One contact on this relay, namely normally-open contact TRSa will thereupon be closed in the alternating current part of the circuitry, and this in turn will energize relay CR3. This relay has a holding circuit through its Contact CRSa and a normally-closed contact CRZa, which latter contact is controlled by relay CRZ, located in the main-drive directcurrent portion of the circuit. Simultaneously another and normally-open Contact CR3b will be closed by relay CR3, thereby closing the circuit of relay CR1, located in the pull-roll direct-current portion of the circuits. Relay CRI will then close normally-open clutch CRla, and open normally-closed contact CRlb, thereby actuating the pull-roll brake d8v and opening fthe pull-roll clutch 45 through energization respectively of the brake 107 and clutch 108. This results in step-rotation of the pull-roll shafts by an amount corresponding to one stitch spacing.

Meanwhile, another contact TRSb, operated by relay TRS and located in the main-drive direct-current circuit, will cause relay CR4 to be energized through normallyclosed contact CK2/5, which is controlled by relay CRZ. As relay CR4 is energized, another relay TR6, connected in parallel therewith, will also be energized, thereby closing contact TR6a (in the alternating current part of the circuit) and this in turn will energize the target latch solenoid 192. By this time the step-rotation of the pull rolls will have advanced the carton blank to a position against the target plate and ready for the first stitch.

Reverting to relay CR4, this acts to open nomallyclosed contact CRla for the main drive brake and at the' same time closing normally open contact CR4b for causing the main drive clutch to be energized, and engagement ot this clutch starts the stitcher head.

After each actuation of the stitching head, the pull rolls again step-feed the carton blank and the machine continues thus to run until the cycle-monitor 63 in effect counts out the preset number of stitches. 0n the last count, a microswitch (which is mechanically held open normally) in the monitor device 63, momentarily closes, thus energizing relay CRZ, which in turn opens the circuit at Contact CRZb, thus deenergizing relays CR4 and TR6, and thereby acting to release the main drive clutch and apply the brake, thus stopping the stitching. Simultaneously, opening of the circuit of relay CRS (at contact CR2a) allows contact CRSIi-to open, releasing relay CRI and causing the pull-roll brake to release and the pull-roll clutch to engage, which in turn allows the pull rolls to rotate continuously for advancing and discharging the carton blank, the joint of which has now been stitched. The cycle of operation is thus completed and the machine -is ready Yto receive the next carbon blank.

In preparing the machine for operation with carton blanks of a predetermined size, the cycle-monitor counter 63 is rst adjusted to count the desired number of stitches. The spaces between the upper and lower pull rolls is then adjusted by adjusting the hand knob 73', as shown in FIG. 5. Side guides for thecarton blank may be provided, as indicated at 126 and 127 (FIG. 2) and these may be mounted .and adjusted in accordance with previous practice with this class of machine. The desired spacing of the stitches may be then adjusted by turning the adjustment knob means at 58 (FIGS. 5 and 6). The position of the target plate 87 may .then be adjusted by turning the handle 93 on rod 92 (FIG. 1l), this adjustment being made so that the space between the stitch position and the target will be a predetermined distance greater than the length of the flap on the carton, which aip advances in front of the position where the joint on the carton is to start, and this distance depending on how near it is desired to have the rst stitch to be spaced away from the flap crease on the carton. After these adjustments are made, the sourcer of power may be connected to the circuits of FIG. 15, and the main motor start-button actuated ,to start operations, as above described.

Although a certain particular embodiment of the invention is herein disclosed in detail fo-r purposes of explanation, various modifications thereof, after study of this specification, will be apparent to those skilled in the art to which the invention pertains. For example, while various switch and relay means are above specified for controlling the circuits, other or generally equivalent forms of transducer means might be used, depending, among other factors, on whether it is preferred to use alternating or direct current as the source of Vsupply or in the circuits for controlling the clutches and brakes. Also other forms of ratchet or ratchet-like means might be used in lieu of the above-mentioned sprag type clutch 61, for example.

What is claimed and desired to be secured by Letters Patent is:

1. In a wire-stitching machine having a stitcher head for applying stitches to a carton blank and means for feeding said blank stepwise to and past said stitcher head during the stitching operation, means for locating the first stitch in a seam, comprising a target plate, means pivotally mounting said target plate to be engaged by the lleading edge of a blank at the start of the stitching operation, means normally biasing said target plate into the path of travel of a carton blank moving through said machine, means normally holding said target plate in optarget mounting means adapting said target plate for movement with saidengaged carton blank, switchmeans, means mounting said switch means to be contacted as said target is moved by said engaged carton, and an electrical operating circuit including selectively operative means for said stitcher head and feed means and relay -means for releasing said target holding means whereby continued movement of the carton blank during the stitching operation rotates said target out of the path of travel thereof until said blank has traveled therepast at the end of the stitching operation.

2. In a wire-stitching machine having a stitcher -head for applying stitches to workpieces and means for feeding said workpieces stepwise to and past said stitcherfhead during the stitching operation, means for locating the first' stitch in a seam, comprising a target plate, means pivotally mounting said target plate to be'engaged by the target plate into the path of vtravel of a workpiece moving through said machine, latch means normally'holding said target plate in operative workpiece-engaging position, support means for said target mounting means adapting said target plate for movement with said engaged workpiece, means for adjustably positioning said target plate to vary its distance from the position of the stitcher head to accommodate workpieces of different dimensions, switch means, meansmounting said switch means to be Vcontacted by said target support means as said target is moved by said engaged workpiece, and an electrical operating circuit including electrical means for controlling the operation of said stitcher head and for also controlling the means for advancing the workpieces, responsive to engagement of a workpiece with the target means, and relay means for releasing said latch means upon application of the first staple by lthe stitcher head and to permit the workpiece to pivot said target out of the path of travel thereof and advance past the target` for receiving subsequent staples. Y

3. In a machine having a stitcherhead for applying a succession of staples to a carton blank, apparatus for operating and controlling the cyclic operation thereof, comprising motor drive means, a drive shaft for the stitcher head, electromagnetic brake and clutch means for normally'retaining said shaft against rotation and then connecting said drive means to said shaft at a pre-selected time during a machine cycle, pull rolls for advancing the blanks seriatim past the stitcher head, shaft means for driving said pull rolls, electromagnetic clutch and brake means for normally connecting the pull roll shaft means to be driven by said drive means and for resisting rotation of the pull roll shaft means at said pre-selected time during the machine cycle; linkage means interconnecting said stitcher head drive shaft and said pull roll shaft means for applying indexed movements to the pull roll shaft means, thereby operating said pull rolls and stitcher head in timed intermittent relationship during the stitching operation, a target plate, means pivotally mounting said target plate to be engaged by the leading edge of a workpiece at the start of the stitching operation, spring means -erative blank-engaging position, support means for said normally resiliently urging said target plate into the path of travel of a blank moving through said machine, latch means normally holding said target plate in operative blank-engaging position, support means for said target mounting means'adapting said target plate for movement with said engaged blank, means for adjustably positioning said target plate to vary its distance from the position of the'stitcher head to accommodate blanks of different dimensions, switch means, means mounting said switch means to be contacted by said target support means as said target is moved by said engaged blanks, an electrical operating circuit including said switch and associated electrical means for actuating said electromagnetic clutches and brakes at said predetermined time to interrupt normal condition thereof, relay means .for releasing said latch means upon application of the first staple by the stitcher lhead and to permit the workpiece to pivot said target out of the path of travel thereof and advance past the target for receiving subsequent staples, a cycle-monitoring device in said operating circuit and operatively connected to said stitcher head for recording successive actuations of said stitcher head, and means controlled by said device for energizing said clutches and brakes to restore them to normal condition'at the end of the stitching operation after said monitoring devicehas counted a selected number.

j References Cited by the Examiner UNITED STATES PATENTS 2,785,403 v 3/57 Harred 1-104 2,908,011 10/59 Mott 1-106 GRANVILLE Y. CUSTER, JR., Primary Examiner. 

1. IN A WIRE-STITCHING MACHINE HAVING A STITCHER HEAD FOR APPLYING STITCHES TO A CARTON BLANK AND MEANS FOR FEEDING SAID BLANK STEPWISE TO AND PAST SAID STITCHER HEAD DURING THE STITCHING OPERATION, MEANS FOR LOCATING THE FIRST STICH IN A SEAM, COMPRISING A TARGET PLATE, MEANS PIVOTALLY MOUNTING SAID TARGET PLATE TO BE ENGAGED BY THE LEADING EDGE OF A BLANK AT THE START OF THE STITCHING OPERATION, MEANS NORMALLY BIASING SAID TARGET PLATE INTO THE PATH OF TRAVEL OF A CARTON BLANK MOVING THROUGH SAID MACHINE, MEANS NORMALLY HOLDING SAID TARGET PLATE IN OPERATIVE BLANK-ENGAGING POSITION, SUPPORT MEANS FOR SAID TARGET MOUNTING MEANS ADAPTING SAID TARGET PLATE FOR MOVEMENT WITH SAID ENGAGED CARTON BLANK, SWITCH MEANS, MEANS MOUNTING SAID SWITCH MEANS TO BE CONTACTED AS SAID TARGET IS MOVED BY SAID ENGAGED CARTON, AND AN ELECTRICAL OPERATING CIRCUIT INCLUDING SELECTIVELY OPERATIVE MEANS FOR SAID STITCHER HEAD AND FEED MEANS AND RELAY MEANS FOR RELEASING SAID TARGET HOLDING MEANS WHEREBY CONTINUED MOVEMENT OF THE CARTON BLANK DURING THE STITCHING OPERATION ROTATES SAID TARGET OUT OF THE PATH OF TRAVEL THEREOF UNTIL SAID BLANK HAS TRAVELED THEREPAST AT THE END OF THE STITCHING OPERATION. 